[CINC] CINMS onGray Migrations-2012

[Mr Zalophus]

Colleagues,

I realize that our knowledge of gray whale feeding is in a state of flux,
as is perhaps the feeding habits of the species.  But after a very short
examination of the scientific literature (using google scholar, searching *
Macrocystis* + *Eschrichtius*), I find zero peer reviewed journal articles
that support the claim made in this NOAA publication that gray whales "feed
on kelp" (second to the last paragraph in Paul's copied excerpt).  Frankly,
I have never seen a shred of evidence that gray whales, or any baleen
whales, are vegetarians.  Perhaps the NOAA author meant to say that gray
whales feed on amphipods and swarms of crustacean larvae associated with *
Macrocystis*. Who knows?  If anyone can show me a peer-reviewed journal
article that documents gray whales "feeding on kelp,"  I'd love to see it
and re-calibrate my old mindset. Otherwise, perhaps NOAA could be convinced
to edit that sentence so as to not put out false information?

Best regards,
Bob Perry
Condor Express and
UCLA OceanGLOBE

On Sat, Jan 26, 2013 at 7:39 AM, paul jr petrich <ppetrich39 at me.com> wrote:

> Hi All,
>  This is an excerpt from our CINMS summarizing official NOAA data about
> the most recent research on Gray Whale migrations. The link I passed on to
> Cubby in my previous email last night has the whole article. The 2008
> American Cetacean Society Conference focused on Gray Whale research, and
> hit upon all the calving and feeding issues discussed by Hal, Marty, and
> Cubby, except the new reevaluations about routes through our Channel
> Islands. If you want specific references to abstracts about those studies,
> let me know ( from 2008 ). Cubby says he emailed Peter about the specific
> studies pertaining to the local routes .  Keep on Swimin, Paul
>
>
> Whales arrive at Santa Barbara Island from a variety of directions and
> pass along either (western/eastern) shore. From Santa Barbara Island, most
> head for Santa Catalina Island and pass along the seaward shore.
>
> Once past the southern Channel Islands (Santa Catalina and San Clemente),
> most whales return to the coast. Some whales continue on into the Sea of
> Cortes, but most spend their winters in and near lagoons on the west coast
> of Baja California and the mainland coast of Mexico near Yavaros.
>
> It has long been believed that most gray whale offspring (calves) are born
> in Mexican waters in and near the lagoons. But more recent studies have
> revealed that a higher than expected number of calves are actually born
> during the southern migration, as far north as southern Oregon. Some
> mothers and calves have been spotted passing south through the Channel
> Island sanctuary waters.
>
> Gray whales begin leaving the lagoons for the northward migration as early
> as mid-January; so the beginning of the northbound migration overlaps
> slightly with the end of the southbound migration near Baja California and
> Southern California in January and February. The northward migration is
> shorter than the southward migration, and it occurs in two distinct waves
> or 'pulses'. The earlier pulse includes a larger cross section of the whale
> population. The later, smaller pulse consists primarily of females and
> their calves.
>
> The occasional observation of females and calves or yearlings in the same
> kelp areas off the Channel Islands on successive days has led to
> speculation that quiet kelp beds<http://channelislands.noaa.gov/animals/graywhal.html> are
> of special importance to newborn and juvenile whales during spring. Given
> that 60% of the kelp beds in theSCB (the Southern California Bight--which
> extends from Point Conception to Cabo Colnette, Baja California) are in
> CINMS waters, some young whales might be expected to linger there. One
> reason the northbound migration takes longer is probably due to whales
> stopping to feed on kelp, which is more bountiful in the spring.
>
> As with the fall/winter migration, during the spring/summer migration some
> gray whales do not complete the migration to subarctic or arctic waters,
> electing instead to spend summer and/or fall in the waters of California,
> Washington, British Columbia, or Alaska. The number of animals in these
> "summering" populations appears to be increasing, along with the growth of
> the population at large (around 25,000 gray whales in the North Pacific as
> of 1996).
>
>
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